A trust of massa



To allwhom z't'm'ay concern: t

Be it known that I, ELIEL L. $I-IARPNE0K, a citizen of the United States of America, and a resident of Bakersfield, in the county of Kern and State of California, have invented a new and useful'Plastic Composition, of which the following is a specification.

an improved composition that can be used for paving roadways, streets, and sidewalks,

The composition comprises a finely di-' v vided filler composed of any soil, sand,

earthy matter, or mixture thereof, a mineral asphaltie binder, sulfate of aluminum, also powdered limestone, for instance in the form of dolomite or marble dust.

- fThe filler which forms approximately 80% to 85% of the whole amount, is screened so that it is. a uniformly fine mass This is heated and thoroughlydried to 'remove all moisture before being mixed. In mixing, the filler is heated to about 300 F., and to this is added from 7% to 15% mineral asphalt binder, also heated to the same degree, the amount used depending on what amount the filler will absorb. Approximately 2% of sulfate of aluminum is added About 6% of powdered limestone, as for instance, dolomite or marble dust, may be also added while heatmg.

the composition hard, itwould be only nec- I essary to add sulfur to the composition, but

sulfuigalso makes it brittle, as well as hard, and I find that sulfate of copper, while it tempers or-hardens the asphaltum, leaves it in a more or less brittle condition. The sulfate of aluminum, however, hardens the asphaltum, and also renders it very tough and not brittle, so that the composition when T acted upon by the sulfate of aluminum has atoughness like rubber which is of greater importance and value in paving roads and streets as'it prevents the cracking of the surface which is bound to occur if the com position is brittle. I prefer to use the lime stone in the form of marble dust, inasmuch as this marble dust when incorporated in the composition makes the composition more dense and more impervious to moisture and The object of this invention is to provide vents it from cracking or If it was simply a question of making ELIEL SHARPNECK, or BAKERSFIELD, CALIFORNIA, IASSIGNOR 'IO ROMANITE COMPANY or AMERICA, oFBos'rou, MASSACHUSETTS,- A nurse or {MASSA- cnosn'rms. v i

a PLASTIGQOMPOSITION. -Jl,$l5,34l2. Specification L i Patent Patented Sept. 9, 1919.

No Drawing. Application filed piecemeal- 27, 1917. serial No. 209,106.]

also acts to harden the mass to a certain ex relatively light roller.

is to be understood that in laying pavements, a foundation courseof about 3 thick and a wearing surface of about '2" in thickness are used, the wearingsurface or layer being laid upon the foundation course after the latter has been rolled. The

Wearing layer is spread over the foundation layer or course at about 300 F. and when rolled the two courses or layers will fuse together in oneinseparable unit from curb to curb. The use of aluminum sulfate hardens, toughens and strengthens the asphalt/and the entire paving mixture, so that itv isrendered strong and absolutely immune to heat, cold and moisture, and pre- Marble dust, limestone, .or dolomite can be used as desired, as dolomite is a variety of magnesian limestone. This crushed limecontaining rock assists in making the mass more dense by its chemical action when comgettiug soft.

bimed with asphalt and sulfate of aluminum.

Of course, when I refer to sulfate of aluminum, I includesuch an ingredient as alum, as the latter is a double sulfate of aluminum with certain other elements.

I am aware that it has been heretofore proposed to use sulfate of copper in combination with an earthy filler and asphaltum. The action of the copper salt is to harden the asphaltum. There is an oxidizing effect,

due to the withdrawal of hydrogen from the hydrocarbon colloids and dispersoids, which make up the body and give character to all asphalts. Copper sulfate crystallizes with fourmolecules of water and when the salt is introduced into a hot asphalt batch at approximately 300 to 400 '1 the water of crystallization is at once liberated, the water producing a foamy condition of the asphalt, which is advantageous and takes part in the hardening reactions immediately occurring. I have found by actual tests, however,

I produced by copper sulfate. Whereas'copcrude aluminum sulfate, which hardens the asphalt to a hardness more than twice that per sulfate contains four molecules of water of crystallization, aluminum sulfate contains eighteen molecules, 'so that on heating this compound, the aluminum sulfate melts relatively large proportion of afinely in its own water of crystallization, which is not the case with copper sulfate. Thus, an .evendistribution of the aluminum sulfate is secured throughout the asphaltic mixture immediately upon the addition of the aluminum sulfate. Weight for Weight, the aluminum sulfate will produce twice as much result as copper sulfate and at a much lower cost.

, Having thus described my invention, What I claim as new therein and desire to secure byv Letters Patent is 1. A plastic composition comprising a divided, earthy filler, mineral asphalt, and

' sulfate of aluminum intimately combined. .25 i 4 therewith.

2. A plastic composition comprising a 'relatively large proportion of a finely.

divided, earthy filler, mineral asphaltum,

sulfate of aluminum intimately combined.

. eral asphalt, sulfate f aluminum,

, mineral asphalt, about 2% therewith whilein a highly heated'condition, and finely crushed limestone.

3. A plastic composition comprising 80 to 85% of a finely divided, earthy filler, 1nineral asphaltum, and sulfate of aluminum.

4. A plastic composition comprfising 80 to 85% of a finely divided, earthyfiller, minand finely crushed limestone.

5.- A plastic composition comprising 80 to 85% of finely divided filler, 12 to 7% of of sulfate of aluminum, .and about. 6% of finely crushed limestone.

6. A method of forming a plastic composition consisting in heating a finely divided 300 F.', adding thereto'a mineral asphaltic binder heated to the same degree, and sulfate of aluminum and stirring the mass while heated until agitation ceases.

In witness whereof, I have hereunto signedmy name in the presence of two subscribing witnesses.

ELIEL L. SHARPNEGK. [1 s.] Witnesses:

. IRMA V. MYER,

Mrs. E. L. SHARPNECK.

filler to a temperature of approximately. 

